Honestly a species-level option for Greater Prairie-Chicken should not even exist.
It existed prior to 2024 for European entries, of which there are several former holdings that I guess couldn't be identified to subspecies or were a generic population. For current US holdings though, I agree there probably aren't any that can't be narrowed down to either
attwateri or
pinnatus.
Now some more birds:
Crowned Cranes: From previous discussion, it was suggested that most, nearly all or possibly all Gray Crowned Cranes are the East African subspecies (
Balearica regulorum gibbericeps) and same for Black Crowned Cranes with nominate (
B. pavonina pavonina). Currently US entries for both species are split - randomly, it seems - between species-level and those particular subspecies. Do we have confirmation that they are all subspecific? They really should all be listed together under one option, there's not two breeding groups of generic and subspecific.
Gentoo Penguin: last I checked the US has both subspecies (
Pygoscelis papua papua and
P. p. ellsworthi) and they are managed separately. I don't think most zoos specify publicly which one they have, which is typical. Currently there are 3 listed for
papua, 4 listed for
ellsworthi, and 14 listed at species level - including 3 of the 4 listed for
ellsworthi.
Southern Rockhopper Penguin: I've seen two suggestions here: one is that the entire population is
Eudyptes chrysocome chrysocome and should be listed as such, and another that there might be a small number of
E. c. filholi and
chrysocome x
filholi hybrids (with Fort Worth being the specific zoo cited as possibly having them, IIRC). Currently 11 zoos are listed for
E. c. chrysocome and 5 are listed at species level, 3 of which are also in the 11 listed to subspecies.
Boat-billed Heron: I've heard that at least some of the US population is the Honduran subspecies (
Cochlearius cochlearius ridgwayi) but is that true, and does this apply to all or just some?